Internal vs External trans filter 1992 Legacy Wagon AWD

[jakimiakj]

I have been told before that all i have to change is the external trans filter on my 92 legacy L awd wagon.

It has a filter that is up by the front left subframe, it is like the fuel filter, with and in line and out line.

I have changed this before, and the fluid. But she is getting older 171k and starting to have issues in cold weather, no hard shifting on a regular basis, occasionally when I get on her hard to pass it will down shift a little hard but even then most times she does this seamlessly. The issue in the cold seems like the torque converter not engaging fully, When I get on the freeway or get up to speed she seems to run a few thousand rpm's higher than normal until it gets warm then everything is normal again.

Should I bother with the internal filter is my primary question.

And if you have any confirmation if that issue sounds related to torque convereter or if it is something else.


Thanks

[bcmaxx]

I have been told before that all i have to change is the external trans filter on my 92 legacy L awd wagon.

It has a filter that is up by the front left subframe, it is like the fuel filter, with and in line and out line.

I have changed this before, and the fluid. But she is getting older 171k and starting to have issues in cold weather, no hard shifting on a regular basis, occasionally when I get on her hard to pass it will down shift a little hard but even then most times she does this seamlessly. The issue in the cold seems like the torque converter not engaging fully, When I get on the freeway or get up to speed she seems to run a few thousand rpm's higher than normal until it gets warm then everything is normal again.

Should I bother with the internal filter is my primary question.

And if you have any confirmation if that issue sounds related to torque convereter or if it is something else.


Thanks

I had my 92 legacy internal filter out after it started to lose function, fluid was very dirty but the internal filter was clean. I thing the external filter does a very good job

[Legacy777]

The "filters" are more just screens than filters. The external filter was added on by the factory to catch shavings or debris when new. Subaru doesn't recommend changing that external filter, so if you've changed it once already I wouldn't bother with it again. The internal screen just prevents picking up metal chunks. As I mentioned it's a screen, so there's really nothing to replace. 9 out of 10 times that screen is going to be perfectly clean. The screen mainly protects against further transmission damage if something happens. Again, it's not something I'd recommend replacing.

As to what you're describing, it sounds normal. The transmission control unit is designed to not lock up the torque converter when fluid temps are below a certain point. This is done to speed up the time it takes the fluid to get to normal operating temperature. When this is occurring RPM's will be higher than normal. Additionally, the TCU may keep the transmission from shifting into 4th gear until transmission temps reach a certain point. Again, this is to speed up the time it takes the fluid to reach normal operating temperature.